Anticipation switch



Aug. 1, 1961 F. OSTEYEE ANTICIPATION SWITCH Filed June 30, 1960 INVENTOR. LEON E OSTE EE United States Patent 2,994,751 ANTICIPATION SWITCH Leon F. Osteyee, San Luis Obispo, Califi, assignor to the United States of America as represented by the Secretray of the Air Force Filed June 30, 1960, Ser. No. 40,126 4 Claims. (Cl. 200-87) This invention relates to a switch which anticipates its own closing time.

One object of the invention is to provide a switch capable of closing its contacts at some predetermined time prior to an arbitrary zero regardless of the speed of approach of its two contacts.

This and other objects will be more fully understood from the following detailed description taken with the drawing, wherein:

FIG. '1 shows a top view of the switch with the top plate and driving gear removed, and

FIG. 2 shows a sectional view along the line 22 of FIG. 1 with the top plate and driving gear in place.

There is sometimes a known time delay between the closing of the switch contacts and the operation of equipment in the performance of a desired function such as in an airborne toss bomb computer. With this fixed time delay the time between the closing of the switch and the performance must remain constant regardless of the speed of advance of the contacts toward closure. If the contacts were to remain stationary, the time from closure to the Zero time would decrease as the speed of approach increases. To compensate for this the contacts of the switch of this invention are made to close early.

Referring more particularly to FIG. 1 of the drawing, reference number refers to an anticipation switch having a cylindrical housing 11, with a top plate 12 and a bottom plate 13, both shown in FIG. 2.

A pair of contacts 14 and 15 are made to approach each other to close at a predetermined time prior to an arbitrary zero time regardless of the speed of approach of the two contacts.

A support is secured to the bottom plate 13 by means of screws 21, one of which is shown. The support 20 has two cross pieces 23 and 24 supported between two upright members 25, one of which is shown in section in FIG. 2. An internally driven gear 26, upon which contact 14 is mounted, has a shaft 27 supported by hearing 28. A shaft 30 is driven from a shaft 34 by means of a driving gear 31 and a gear 32. Shaft 30 is supported by bearings '35 and 36. An idler gear 37 is driven from shaft 30 by gear 38. Two pairs of permanent magnets 40 and 41 having gaps 42 therebetween, one of which is shown in FIG. 2, are mounted on arms 45 which are integral with shaft 30.

The other contact 15 is mounted on an arm 46. An identical arm 47 is located opposite arm 46. Copper plates 48 and 49 are mounted on arms 46 and 47 in the manner shown in FIG. 2. These may be secured by any well-known means such as by riveting. The arms 46 and 47 are supported by two insulating bearings 50 and 51. The gearing is chosen so that the speed of contact 14 will approach contact 15 at a speed which is the same as that of shaft 34 and so that arms 45 with the attached magnets approach the copper plates 48 and 49 at a speed greater than the speed of shaft 34 which for one device built was four times that of the shaft 34. While the gearing shown is friction gearing, it is obvious that other gearing might be used. The magnets 40 and 41 together with copper plates 48 and 49 constitute an eddy current mechanism such as found in some magnetic tachometers wherein the eddy currents produced by the copper paddles passing through the magnetic gaps ice 42 create a torque, against the resisting torque of spring 52, which is proportional to the speed of shaft 34. Thus the speed of approach of contacts 14 and 15 will determine their closing time.

Electrical connection is made to the contact 14 through the housing and the gear 26 by means of a contact 53. Electrical connection is made to contact 15 by means of terminal 55 and torque spring 52 which are connected to arms 46 and 47 at 54.

There is thus provided a switch capable of closing its contacts at some predetermined time prior to an arbitrary zero, regardless of the speed of approach of its two contacts.

While one specific embodiment has been described in some detail, it is obvious that numerous changes may be made without departing from the general principles and scope of the invention.

I claim:

1. An anticipation switch comprising; means for producing a magnetic field across an air gap; an input shaft; a pair of switch contacts; an eddy current plate adapted to pass through said air gap; rotatable means for supporting said eddy current plate; the first of said contacts being located adjacent said eddy current plate; means driven by said input shaft for supporting the second of said pair of contacts and for moving it toward said first contact in response to rotation of said input shaft; means, responsive to said input shaft, for moving said magnetic field producing means past said eddy current plate at a speed greater than said input shaft whereby the eddy current plate passes through said air gap to thereby produce a torque on the means supporting said eddy current plate; means, connected to said eddy current plate supporting means, for providing an opposing torque and means for providing electrical connections for said switch contacts.

2. An anticipation switch comprising; means for producing a magnetic field across a pair of air gaps; an input shaft; a pair of switch contacts; a pair of eddy current plates adapted to pass through said gaps; rotatable means for supporting said eddy current plates; the first of said contacts being located adjacent one of said eddy current plates; means, driven by said input shaft, for supporting the second of said pair of contacts and for moving it toward said first contact in response to rotation of said input shaft; means, responsive to said input shaft, for moving said magnetic field producing means past said eddy current plates at a speed greater than said input shaft to thereby produce a torque on the means supporting said eddy current plates when said eddy current plates pass through said air gaps; means, connected to said eddy current plate supporting means, for providing an opposing torque and means for providing electrical connections for said switch contacts.

3. An anticipation switch comprising; a first pair of permanent magnets having an air gap therebetween; a second pair of permanent magnets having an air gap therebetween; a first and second eddy curent plate adapted to pass through said air gaps; rotatable means for supporting said eddy current plates; a pair of switch contacts; the first of said contacts being located adjacent one of said eddy current plates; means, driven by said input shaft, for supporting the second of said pair of contacts and for moving it toward said first contact in response to rotation of said input shaft; means, responsive to said input shaft, for moving said permanent magnets past said eddy current plates at a speed greater than said input shaft whereby the eddy current plates pass through said air gaps to thereby produce a torque on the means supporting said eddy current plates; means, connected to said eddy current plate supporting means,

for providing an opposing torque and means for providing electrical connections for said switch contacts.

4. An anticipation switch comprising; a first pair of permanent magnets having an air gap therebetween; a second pair of permanent magnets having an air gap therebetween; a first and second eddy current plate adapted to pass through said air gaps; a rotatable support for said eddy current plates; a pair of switch contacts; the first of said contacts being located adjacent one of said eddy current plates; means, driven by said input shaft, for supporting the second of said pair of contacts and for moving toward said first contact in response to rotation of said input shaft; means responsive to said input shaft for moving said permanent magnets past said eddy current plate at approximately four times 15 2,209,368

the speed of said input shaft whereby the eddy current plates pass through said air gaps to thereby produce a torque on said rotatable support; a spring, connected to said rotatable support, for providing an opposing torque and means for providing electrical connections for said switch contacts.

References Cited in the file of this patent UNITED STATES PATENTS 1,161,932 Du BOiS NOV. 30, 1915 2,162,490 Mikina June '13, 1939 2,206,696 Hall July 2, 1940 Whittaker July 30, 1940 

